TUT And CT's Arm Program

CT wrote:

“1) Start by selecting the appropriate load for maximum hypertrophy (something like 70-80% for beginners, 80-90% for intermediates, 85-95% for advanced)”

“once a trainee is past the beginner stage, an external loading of less than 80% of his maximum doesn’t lead to optimum gains.”

Looking at the arm program said he’s doing right now in the dialogs, this means he’s doing 10 reps with a 501 tempo at (at least) 80%? Thats nuts! I’d only get half of those reps.

So if thats the case, should i just do less reps to stay within that load range? I could always add more sets, or am i missing something here?